Hydrogen Fuel for Aircraft: Changing the Way Planes Work and Look

Hydrogen is seen as one of the major paths forward to net zero emissions in the aviation industry. It is believed to be an effective solution to climate change caused by passenger air travel, which accounts for about three percent of global carbon emissions. While new technologies will be needed to reach net zero, transitioning to hydrogen would require a significant rethinking of aircraft design. Airbus is currently testing the use of hydrogen fuel in real-world conditions with a modified A380 airliner. This test will allow researchers to better understand hydrogen combustion in flight and help develop a zero-emissions aircraft that Airbus plans to have in service by 2035.

How Hydrogen Fuel is Changing Aircraft Design and Function

The Growing Need for Sustainable Solutions

As concerns about climate change continue to mount, the aviation industry is under increasing pressure to find more sustainable solutions. Passenger air travel is one of the biggest contributors to carbon emissions, accounting for approximately three percent of global emissions in 2021. While cutting back on air travel and investing in more efficient planes can help to reduce emissions, new technologies are necessary to reach the goal of net zero carbon emissions by 2050.

While several solutions, such as battery-powered air taxis and sustainable aviation fuels, can help to cut emissions, hydrogen is seen as one of the primary paths forward. Hydrogen fuel can be used across the industry, from shorter regional hops to longer flights with larger planes, making it a potentially effective solution to reduce emissions.

Testing Hydrogen-Powered Flight with Airbus

Airbus, one of the world’s leading aircraft manufacturers, is testing the potential of hydrogen fuel with a modified A380 airliner. The aircraft will be equipped with an additional hydrogen-combustion engine on the outside and monitoring equipment to test hydrogen-powered flight in real-world conditions.

The placement of the hydrogen engine at the top of the plane and in the back, just in front of the tail, is significant. Separating it from the four engines on the wings that burn traditional jet fuel allows for emissions sampling from the hydrogen fuel by another plane flying behind the A380 in flight.

Understanding Emissions from Hydrogen Combustion

While burning liquid hydrogen doesn't produce CO2, researchers still need to understand more about the emissions from hydrogen-powered flight. Hydrogen engines still produce some nitrous oxides and water vapor, which act as greenhouse gases in the atmosphere. By testing the hydrogen engine in real-air conditions, Airbus can better understand how to most efficiently power a hydrogen-powered plane.

The Challenges of Hydrogen Fuel Storage

One of the biggest challenges of transitioning to hydrogen fuel for aircraft is storage. Hydrogen is less dense than traditional jet fuel and takes up at least four times more space when comparing the amount of fuel needed to generate the same power. Hydrogen also requires high-pressure containment and low temperatures, which means it is kept in larger, cylindrical tanks instead of the wings of traditional aircraft designs. This requirement can significantly limit the remaining space, reducing passenger capacity by a third or more.

Redesigning Aircraft for Hydrogen Fuel Storage

To address the challenges of hydrogen fuel storage, aircraft will likely need to be completely redesigned. One of the concept planes Airbus revealed last year, the blended-wing body design, offers an example of a configuration that would better use space for fuel storage. This model may also have other benefits over traditional plane designs, like increasing aerodynamic efficiency by ten percent or more.

Conclusion

Hydrogen fuel has the potential to revolutionize the aviation industry and pave the way for a zero-emissions future. However, transitioning to hydrogen fuel requires significant changes in aircraft design and function. The current test program by Airbus aims to help the industry better understand how to use hydrogen fuel in flight.